Magnetic separator



NOV- 29, 1932. w. c. BUTTRON 1,839,349

MAGNETIC SEPARATOR l Filed May 14. 1928 2 sheets-sheet 1 NVENT OR Wl/M C. MM

ATRNEY BYY Nov. 29, 1932. w C, BUTTRON 1,889,349.

MAGNETIC SEPARATOR Filed May 14, 1928 2 Sheets-Sheet 2 IN VEN TOR WMM C. ,ga/55;

Patented Nov. 25", 1932 UNITED sTATEs PATENT oFFicE y WILLARD C. BUTTRON, OF ALBANY, NEW YORK, ASSIGNOR T GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK MAGNETIC SEPARATOR Application filed May 14,

This invention relates to magnetic separators particularly adapted for use inconnection with railway coaling stations, coal crushers, pulverized fuel units, stokers and the like.

Among the more important objects of the invention is the provision of a .magnetic separator of the character in question which is simple and rugged in construction and more effective than those heretofore employed in removing stray bolts, rods, tramp iron and the like from the coal.

The more specific objects and advantages will be apparent from a consideration of the following descriptiontaken in connection with the accompanying drawings which 1llustrate the preferred embodiment as well as a modification in construction? Figure 1 is a somewhat diagrammatic s ide elevation of a railway or locomotive coaling station with my improved separator applied thereto, a portion of the coal bin of the station being broken away to disclose Jthe mounting of one of the separators therein;

Figure 2 is a longitudinal sectional view of the preferred form of the separator;

Figure 3 is a plan view of the saine;

Figure 4 is a view, partly in section and partly in elevation, of the separator shown in Figs. 2 and 3 as applied to one of thev delivery spouts of a coaling station; and

Figure' 5 shows a modified form of the invention as applied to one of the delivery spouts of a coaling station.

Referring now to Fig. 1, a coal bin of a railway coaling station is indicated by the reference character 6. This bin is suitably mounted above the tracks 7 on uprights 8. An endless conveyor 9, carrying the buckets 10 is adapted to raise the coal to a point above the bin 6 and feed it horizontally across the floor 11 to the opening 12 therein through which it drops by gravity to pass over the magnetic separator, indicated as a whole at 13, into the bin. The bin is provided with a number of coal delivery chutes which are adapted to discharge the coal into the loco- 50 motive tenders. Each chute 14.- may also 1928. Serial No. 277,594.

be provided with one of my improved magnetic separators 13.

Referring more particularly to Figs. 1, 2 and 3, it will be seen that iny improved separator consists of a plate l5 over which the coal 55 is adapted to pass in being delivered either from the floor 11 into the bin 6 or from the bin 6 into the locomotive tenders. Below the plate 15 I have arranged two electromagnet cores 16 and 17 which extend through e apertures in the plate 15 to a point Hush with the upper surface thereof. These cores as well as the plate 15 are preferably made of relatively soft magnetic iron and the cores are preferably welded to the plate 15 as in- 65 dicated at 18 in order to provide efective magnetic contact therebetween. The ends of the cores remote from the plate 15 are magnetically joined by means of a soft iron bar 19 which is secured to the cores by means 70 of bolts 20. The windings 21 and 22 around the cores 16 and 17 respectivelyare oppositely wound to give the plate ends of the cores opposite magnetic poles, that is, one south and the other north.

In order to separate or magnetically insu late the plate ends of the cores 16 and 17 l have provided an insert 23 of non-magnetic material in the plate 15 between the cores.

1n its preferred form this yinsert 23 is in the 8 nature of a brass strip brazed to the edges of the plate 15 so that the separator as a whole vwill be of a construction which issuciently rigid to withstand the wear caused by the coal dropping thereon and sliding thereacross.

At the lower 'end of the plate l5, which is bent downwardly as indicated at 24, are arranged two additional electromagnets 35, each having two core elements 25 and 26 eX- 90 tending into apertures in the extension of the plate 15 and welded thereto as indicated at 18. Each of these second electromagnets is further provided with a core element 27 which is secured between the ends of the core elements 25 and 26 remote from the plate by means of the bolts 28. The windings 29 around the cores 27 are wound to give the upper core elements 25 the same magnetic polarity which the core 17 presents to the plate. 10

Another brass insert 30 in the plate 15 is rovided between the core elements 25 an 26,

It should also be noted that the extreme lower construction of the plate 15 is to provide a pair of intersecting magnetized surfaces so arranged that the second surface in the line of descent makes a steeper angle with the horizontal than the first is an important feature of the invention. This will be apparent when it is realized that large heavy chunks of coal passing over the first surface at high velocity dislodge tramp iron which may have been attracted from the coal stream. The presence of the second surface inclined at the greater an le serves to attract these dislodged iron ies out ofthe pathway of the descending coal which continues on past the intersection of the two surfaces without coming in contact with the steep surface of the lower in the manner of water passing over a fall.

This efficiency of the function of the second surface is further enhanced b so arranging the magnets with respect to t e intersecting surfaces that the cores 17 and 25 located adjacent each other on oiposite sides of the'line of intersection are o ike polarity. Ithas es 17 and been determined that with the po 25 of like polarity, the descent of any'tramp iron that may have been jarred loose from the upper surface will be greatly retarded,

-netic fiel thus assistin and enabling the lower ma et cores 25 and 26 to attract this iron ftixdm the stream of passing coal into engagement with the lower surface, whilst when the poles 17 and 25 are of unlike polarity the descent of tramp iron jarred loose from ole 17, or passing 1t, will be accelerated and t e speed of its descent increased to suchan extent that it will continue over the line of intersection with the stream of coal, thereby rendering the magnets 25 and 26 ineffective to perform their intended function. Thus, it will be seen that the arrangement of the magnets. with poles of like polari adjacent each other is also an important eature of my improved separator.

In Fig. 4 the separator of Figs. 2 and 3 is shown as applied to a coal delivery chute or spout 14. It should be noted that the se arator in this arrangement is secured to the ower side of the chute by means of bolts 32 and also that the chute is provided with a brass 4insert 33 between the cores 16 and 17 extending at least part way around the chute in order to (prevent shortcircuiting of the magthrough the walls of the chute.

In accordance with the modification in Fig. 5 the cores 16 and 17 are mounted to extend p into apertures in the lower side ofthe chute 14, in which case the chute is preferably constructed of relatively soft or magnetic iron. A brass insert 34 is also provided in the chute endto an upright 37 as indicated at 38. Any

suitable means such as the. chain 39 is provided for retaining the plate 15 at the desred inclination. This inclination may of course vary according to the size and condition ofl the coal.

In considering the operation of the invention it should be borne in mind that coal as it is delivered to the bins of coaling stations usually contains a considerable quantity of tramp iron and the like, which quite obviously might result in serious damage to the stoker elements of Stoker equipped locomotives, as well-as to the grates of any locomotive, if it were not removed.

As fhe'coal is fed across the floor 11 by the buckets 10, it drops onto the separator through the o ening 12 and on account of the inclination o the plate 15 it moves downwardly thereacross in a substantially continuous stream which accelerates and becomes thinner as it approaches the lower end of the plate. Thus the electromagnets are afforded a better opportunity of attracting and retaining the tramp iron, because it is only necessary for them to draw the pieces through a relatively thin layer of coal. As the coal Stream containing iron or other magnetic bodies passes the upper magnets on the plate 15, these magnetic bodies will be withdrawn from the stream of the passing coal and held fast to the plate 15 by magnetic attraction, as is well understood by persons skilled in the art. It is entirely within the realm of possibility that the passageof large heavy chunks of coal will dislodge pieces of iron which may have been attracted into engagement with the late 15, thereby allowing these pieces to be accelerated and carried along with the descendng stream of coal. However, due to the fact that the up r cores 25 of the auxiliary magnets 35 and t e lower core 17 of the main magnets 13 are of like polarity the resultant magnetic fluxes will exert a strong retarding effect on the moving iron as it approaches the intersection 24 of the two magnetized surfaces. This retardation of the swiftly moving iron is effective.l to slow its speed to a value sufficiently low to enable the auxiliary magnets35 to attract the tramp iron from the moving coal stream and to retain it, while permitting the coal itself to continue on uninterruptedly. over the intersection 24 to describe a parabolic path withlas out coming into contact with the lower magnetized surface of plate 15, and it should bev noted that the hook or flange 31 at the bottom of the plate materially assists in retaining such strayv pieces of iron against being displaced by the stream ot' coal which passes this part of the plate in a substantially vertical direction.

In conclusion, it should be noted that the brass inserts in the plate 15 between the north and south poles of the U type of electromagnets 13 and 85 prevent shortcircuiting of the magnetic iields ot these magnets and thus permit their maximum energy to go toward attracting and retaining miscellaneous pieces of tramp iron. It should also -be noted that the relative arrangement of the poles of the magnets 13 and 35 with respect to the flow of coal over the magnetized plate or plane 15 provides for substantially complete utilization of the attractable force of electromagnets of a given capacity of electrical input.

I claim 1. ln apparatus for separating magnetically' attractable materials from other materials, the combination of an inclined magnetizable plate having a pair of apertures therein, a pair of electromagnets below said plate having cores extending into said apertures and associated therewith to provide eli'ective magnetic contact therebetween and a nonmagnetic insert in said plate between said apertures, together with an extension of said plate extending at an angle from an end thereof and other electromagnets associated with said extension.

2. In apparatus for separating magnetically attractable materials from other materials, the combination of an inclined magnetizable plate over which the mixed materials are passed, a non-magnetic insert extending across said plate, a plurality of electromagnets magnetically associated with the plate and arranged to provide opposite magnetic poles on each side of said insert, an extension of said plate extending substantially vertically downward from the lower edge thereof and another electromagnet associated with said extension.

3. In apparatus for separating magnetically attractable materials from other materials, the combination of an inclined magnetizable plate over which the mixed materials are passed, a non-magnetic insert extending across said plate, a plurality of electromagnets magnetically associated with the plate and arranged to provide opposite magnetic poles on each side of said insert, an extension of said plate extending substantially vertically downward rom the lower edge thereof and another electromagnet associated with said extension, together with hook means at the lower extremity of said extension for retaining material attracted thereby.

4. In a magnetic separator the combination of a magnetic plate, a magnet associated with said plate, an extension of said plate extending from an edge thereof at an angle thereto, a non-magnetic insert extending across said extension and magnets magnetically .associated with the extension and arranged to provide opposite magnetic poles at the sides of said insert.

5. In a magnetic separator the combination of a magnetic plate, a magnet associated with said plate, an extension of said plate extending from an edge thereof at an angle thereto,

ya non-magnetic insert extending across said extension and magnets magnetically associated withthe extension and arranged to provide opposite magnetic poles at the sides of said insert, together with a flange at the edge of said extension remote from said plate.

t3. In a magnetic separator, the combination'of a magnetizable plate, a non-ma netic insert extending thereacross, a plurality of electromagnets magnetically associated with said plate and arranged to provide opposite magnetic poles at opposite sides of said insert,'an extension ot' said plate7 a non-magnetic insert extending across said extension and a plurality of electromagnets magnetically associated with said extension and arranged to provide opposite magnetic poles at opposite sides of the insert in said extension.

7. In a magnetic separator, the combination of a magnetizable plate, a non-magnetic insert extending thereacross, a plurality of electromagnets magnetically associated with said plate and arranged to provide opposite magnetic poles at opposite sides of said insert, an extension of said plate, a non-magnetic insert extending across said extension and a plurality of electromagnets magnetically associated with said extension and arranged to provide opposite magnetic poles at opposite sides of the insert in said extension, the electromagnet associated with said plate at the side of its insert adjacent said extension having the same magnetic polarity as the electromagnet associated withv said extension at the side of its insert adjacent the said plate.

8. In a magnetic separator, the combination of a magnetizable plate, a non-magnetic insert extending thereacross, a plurality of electromagnets magnetically associated with said plate and arranged to provide opposite magnetic poles at opposite sides of said insert, an extension of said plate, a non-magnetic insert extending across said extension and a plurality of electromagnets magnetically associated with said extension and arranged to provide opposite magnetic poles at opposite sides of the insert in said extension, together with an upturned flange at the extremity of said extension.

9. In apparatus of the character described a coal chute having a portion inclined with the horizontal and a second portion extending from said first portion at such an angle as to be substantially vertical with the horizontal, a separator comprising a magnetizable member having two portions a pair of surfaces intercepting eac other at an an le substantiall equal to said first mentione angle means or securing the ortions of said member to the portions of said chute respectively, a separate electroma et secured to each of the ortions of said member with the poles o? like polarit of said Ifnagnet adjacent the intersection o said suraces.

10. In apparatus of the character described a coal chute lhaving a portion inclined with the horizontal and a second portion extending from said first portion at such .an angle as to b'esubstantially vertical with the horizontal, a separator comprising a. magnetizable member having two portions providing a pair of surfaces intercepting each other at an angle substantially equal to said first mentioned angle means for securing the portions of said member to the portions of said chute respectively, a separate electromagnet secured to each of the portions of said member with the poles of like polarity of said magnet adjacent the intersection of said surfaces, and mechanical means located at the lower extremity of said member for cooperating therewith to intercept and retain magnetically Aattractable material.

11. A magnetic separator comprising a pair i of intersecting surfaces, a. separate magnet arranged on each of said surfaces to provide poles of like polarity adjacent the intersection of said surfaces and poles of opposite polarity on said surfaces remote from said intersection.

In testimony whereof, I have hereunto signed my name.

WILLARD C. BUTTRON.

providing l 

